1. Field of the Invention
The present invention relates to a spoke, and more particularly to a spoke of a bicycle wheel to enhance the combination between a nut and a threaded segment of the spoke to prevent the nut from loosening from the threaded segment.
2. Description of Related Art
A wheel of a bicycle substantially comprises a rim, a hub and multiple spokes. Each spoke has a mounting end connected securely with the hub and a connecting end. The connecting end is threaded and is connected securely with the rim with a nut. Accordingly, the spokes can provide an excellent supporting effect to the rim and transmits driving power from the hub to the rim to make the wheel rotating and driving the bicycle to move. To keep the safety of riding the bicycle, the wheel has to be an excellent circular condition. However, the nuts of the conventional spokes on a bicycle wheel will be loosened from the treaded connecting ends of the spokes to cause the wheel not kept at the excellent circular condition due to the shock or vibration generated during the riding of the bicycle. Accordingly, the stabilization and safety of riding the bicycle will be badly influenced.
With reference to FIG. 5, a conventional spoke 30 having a loosen-proofing effect comprises a spoke body 31, a mounting head 32 connected with a hub and a threaded segment 33. The threaded segment 33 is connected with a rim with a nut and has a non-threaded buffering section 34 formed between two thread sections including a first thread section and a second thread section adjacent to the spoke body 31. The second thread section has a length longer than that of the first thread section and has a pitch different from that of the first thread section. When the nut is screwed onto and engages the thread sections of the threaded segment 33 of the spoke 30, the non-threaded buffering section 34 will be expanded, shortened or twisted due to the difference between the pitches of the thread sections. Therefore, the threaded segment 33 of the spoke 30 will be deformed due to the elastic stress and torque caused by the deformation of the buffering section 34. The deformation of the threaded segment 33 will make the secure combination between the threaded segment 33 and the nut to provide a loosen-proofing effect, but this also easily cause break or damage to the buffering section 34 due to the stress and torque. When the buffering section 34 is broken or damaged, a new spoke is needed to replace a damaged one, and this is uneconomic and not environment friendly.
To overcome the shortcomings, the present invention tends to provide a spoke to mitigate or obviate the aforementioned problems.